2019年IOAA理论第2题-太阳系天体的引力透镜
|
|
本题目目前没有解答。要不要你来试试！ |
英文题目
2. Deflection of radio photons in the gravitational field of solar system bodies (10 p)
A. Eddington and F. Dyson from Principe, and C. Davidson and A. Crommelin from Sobral, Brazil measured the deflection of light coming from stars apparently very close to the Sun during the total solar eclipse in 1919. The deflection was found to agree with the theoretically predicted value of 1.75".
A light ray (or photon) which passes the Sun at a distance 𝑑 is deflected by an angle
$$Δθ=\frac{4GM}{dc^2}$$
The present-day accuracy of the VLBI (Very Long Baseline Interferometry) technique in the radio wavelength range is 0.1 mas (milliarcsecond). Is it possible to detect a deflection of radio photons from a quasar by (a) Jupiter, (b) the Moon? Estimate the angle of deflection in both cases and mark "YES" or "NO" on the answer sheet.
中文题目
2. 射电光子在太阳系天体引力场中的偏转(10分)
1919年的日全食期间，来自普林西比的A. Eddington 和F. Dyson与来自索夫拉尔的C. Davidson 和 A. Crommelin测量了来自看起来距离太阳非常近的恒星的光的偏转。该偏转角度与理论预测值1.75”一致。
在一定距离内通过太阳的光线(或光子)的偏转角由下式给出：
$$Δθ=\frac{4GM}{dc^2}$$
VLBI(甚长基线干涉测量)技术目前在射电波段中的分辨率为0.1 mas。有可能探测到：
(a)木星
(b)月球
对类星体射电光子的偏转吗?估计两种情况下的偏转角，并在答题纸上标记“是”或“否”。
